Philip Hammond said the bloc was unable to take in millions of people seeking a new life.

Mr Hammond's comments, some of his most outspoken on the subject yet, underscore how the British government is ramping up its anti-immigration rhetoric in response to a spike in migrant attempts to reach Britain via the Channel Tunnel from France.

They are also part of a wider EU trend which has seen Alexis Tsipras say Greece cannot cope with the number of migrants fleeing instability in the Middle East and Africa and German calls for tighter immigration curbs.

"We have got to be able to resolve this problem ultimately by being able to return those who are not entitled to claim asylum back to their countries of origin," Mr Hammond told BBC TV. "That's our number one priority." He said EU laws meant migrants were "pretty confident" they would never be returned to their country of origin.

"That is not a sustainable situation because Europe can't protect itself and preserve its standard of living and social structure, if it has to absorb millions of migrants from Africa," he added.